Positive Phase III results for Pfizer RSV vaccine candidate in older patients

Moving ahead in the race to develop a jab for respiratory syncytial virus (RSV), a market that analysts estimate will generate up to $10 billion of annual sales, yesterday US pharma giant Pfizer (NYSE: PFE) announced positive top-line data from the Phase III clinical trial (NCT05035212) RENOIR (RSV vaccine Efficacy study iNOlder adults Immunized against RSV disease) investigating its bivalent RSV prefusion F vaccine candidate, RSVpreF, when administered to adults 60 years of age or older. The bivalent vaccine candidate is composed of two preF proteins selected to optimize protection against RSV A and B strains.

A pre-planned, interim analysis of Pfizer’s RSVpreF efficacy conducted by an independent, external Data Monitoring Committee (DMC) to assess protection against RSV-associated lower respiratory tract illness (LRTI-RSV) defined by two or more symptoms demonstrated vaccine efficacy: 66.7% (96.66% CI: 28.8%, 85.8%). This positive result enabled Pfizer to look at the more severe disease primary endpoint of LRTI-RSV defined by three or more symptoms, where vaccine efficacy of 85.7% (96.66% CI: 32.0%, 98.7%) was observed. The DMC also indicated the investigational vaccine was well-tolerated, with no safety concerns.

Plans for BLA filing